DE3541142C2 - Control and correction device for the transverse dimensions of rod-shaped products, in particular for confectioning machines for tobacco products - Google Patents

Description

The present invention relates to a control and correction device of the transverse dimensions of rod-shaped products, especially for Packaging machines for tobacco products, which have a surface for Forming a continuous strand, which in Direction of advance of the strand with means for guiding and Folding a paper tape around a filler for the strand is provided, which is an adhesive device for attaching a Adhesive substance on at least one longitudinal edge of the paper tape has a locking device through which the paper tape around the filler to form a continuous strand is closable, and the one Measuring device for detecting the transverse dimensions of the strand has whose signals in a device for correction the transverse dimensions of the strand can be used.

What in the description below with reference to a packaging machine for cigarettes is presented, basically also applies to a packaging machine for Cigarette filter.

Such a control and correction device Cross dimensions of rod-shaped products is from DE-OS 20 17 078 known. A sensing device measures the Diameter of the rod-shaped product, e.g. B. one  Cigarette filter strands by introducing air into a chamber through which the strand runs, the through which Amount of air passing through the chambers with a Enlargement of the strand diameter reduced and thereby There is reason to increase the pressure in the compressed air supply. Depending on the pressure, the movement of a core in a coil generates an electrical signal, which in a Adjusting motor can be used, through which the diameter of the String is correctable.

However, this control system of a pneumatic type proves to be not of a sufficient degree of precision, since the im Pressure values measured inside this chamber significantly the high porosity of the for the production of the continuous strand used paper and also by the Feed speed of the strand is affected will.

Control devices such as these are also known e.g. B. have been described in EP 0 057 992 A1 to control the transverse dimensions of the strand elastic slats are used that have one end are attached to a fixed support and with the at the other end on the continuous strand. medium to detect the change in tension of the slats  electrical signals to indicate the transverse dimensions of the Strangs for any correction work are usable.

It is clear that in a device of this type that Grinding these lamellae on the continuous strand can damage it, especially at Packaging machines for very high cigarettes Speed. It can also vibrate this Slats by moving the strand in relation to this arises, lead to errors in the acquisition, which are then act as a correction error.

DE 27 32 520 B2 describes a device for checking of a strand on different material properties and / or continuously alternating on training successive body in a cigarette filter train known. There is at least one photoelectric Component perpendicular to the longitudinal axis of the strand opposite one light-emitting optical waveguide as a measuring device intended. Between the light emitting Optical fiber and the photoelectric component is the cigarette filter strand passed and depending on Output signal of the photoelectric component is on the material properties of the partially translucent Cigarette filter strand closed. The signals of the Measuring devices are used to make faulty  Weed out filter rods. This device is not intended Acquire transverse dimensions of a filter string.

From DE-GM 18 84 252 is a machine for manufacturing of a continuous string of cigarettes, the one Measuring device made of photoelectric means for scanning the Strength and length of the cigarettes. This is provided that for measuring the strand thickness of the cigarettes this between a test lamp and a photo resistor be performed. If the cigarette is too thick or too thin, too little or Received too much light from the test lamp. This well-known Detection of the strength of a cigarette has now the Disadvantage that only one-dimensional resolution is achieved can be d. H. only those in an orthogonal to the Component of the beam path Strand cross section can be detected. It is therefore in disadvantageously possible that the in the direction of Component of the cross-section of the beam deviates more or less from the target value and that this not from the testing device of the known machine can be determined.  

DE 28 33 118 A1 describes a method and an arrangement to form a strand of smokable, preferably from Existing tobacco fibers are known to be a control device through which the tobacco rod for the Manufacture of cigarettes with constant hardness Strands of cigarettes and thus the cut off Cigarettes can be regulated. For this purpose it is provided that the decrease in excess tobacco from a control signal is controlled depending on the one for a desired hardness value of the cigarette rod predetermined, a defined relationship between the Height of the equalized, undensified strand representing signal and that of the control device generated measurement signal is formed, and that this Control signal the distance of a delivery point from one Strand conveyor in the sense of keeping the Controls strand hardness. To measure the height of the uncoated A tobacco rod is provided with a light source Lens parallel light through a semi-transparent mirror and via a deflecting mirror to a reflection mirror sends. Through the beam path between the Reflection mirror and the deflecting mirror is the Promoted tobacco rod. The reflected rays of light get back to the semi-transparent mirror, which sends them to a photoelectric receiver. This has several staggered one above the other photoelectric element. That way from  Receiver contained signals for the height of the tobacco rod are summed by means of an adder. The The output signal of this adder then represents a measure of represents the height of the tobacco rod.

A capture of other transverse dimensions does not take place optically.

The object of the present invention is in a Device of the type mentioned Use of scanning devices to avoid pneumatic or mechanical type, and a more precise recording of the To enable transverse dimensions.

This object is achieved in that the Control and correction device as a measuring device optical scanners having at least two light sensors contains, essentially in two orthogonal to each other and directions extending to the direction of advance of the strand are arranged, with the first optical scanner  which are orthogonal to its direction of arrangement running plane lying component of the transverse dimension of the Strands detectable and a representative of this component first signal can be generated, and wherein by the second optical scanner in one to its direction of arrangement second component of the orthogonal plane Transverse dimension of the strand can be detected and a second one Component representing a second signal can be generated, that the control and correction device a circuit to process those generated by the two scanners Has signals for the actual diameter, with a through the circuit Control signal for the device for correcting the Cross dimensions of the strand can be generated to a target diameter, and that by this control signal driven device for correction the transverse dimensions of the string of stepper motors driven means for changing the transverse dimensions of the Strands in the first and the second direction.

Further refinements are specified in the subclaims.

The invention will now become an example with reference to the accompanying drawings explained in more detail.

It shows

Fig. 1 shows schematically the arrangement of the apparatus of the present invention to a manufacturing machine for cigarettes,

Fig. 2 shows schematically in an enlarged form and in perspective the apparatus according to the present invention, limited to the main operating parts,

Fig. 3 in blocks, a possible circuit diagram of the device,

Fig. 4 in blocks a further possible shift pattern,

FIGS. 5 and 6 used depending another possible realization form of the device for correcting the transverse dimensions of the strand, as an alternative to that shown in FIG. 2. With reference to FIG. 1, 1 denotes a packaging machine for cigarettes in its entirety. 2 denotes the lower run of a suction belt, which runs at both ends via rollers 3 (only one of them is visible in Fig. 1), while 4 denotes the upper run of a conveyor belt 6 running over a basically horizontal surface 5 , which in its end positions runs over rollers 7 and 8 and is driven by a roller 9 rotating in the counterclockwise direction. 10 with a spool is designated, from which a paper tape 11 for cigarettes unwinds, which is passed through a lay-up roller 12 above the run 4 .

At the point where the strand 4 meets the strand 2 , the latter throws a continuous strand of cut tobacco onto the paper tape 11 for cigarettes. Then the run 4 runs over the surface 5 within a guiding and folding device 60 , which contains a groove, which gradually brings the run 4 itself and thus also the paper tape 11 to a shape which is basically designed as a "U" around the tobacco rod to assume and consequently form a ring-like closed shape, so that the tobacco rod is wrapped in a tubular paper wrapper.

Along the course of the run 4 , an adhesive device is provided, which is designated in its entirety by 62 and which uses a nozzle (not shown in the drawings) to apply a strip of adhesive substance to the inside of one in the two longitudinal edges of the paper tape 11 .

The adhesive device 62 is followed along the course of the run 4 by a device 13 (described in detail below) for correcting the transverse dimensions of the strand which is gradually formed by the folding action of the paper tape 11 around the tobacco rod, and a closing device 14 which is operated by electrically heated Elements the drying of the adhesive substance and consequently attaching the paper tape 11 around the tobacco rod, so that a continuous cigarette rod is formed. This cigarette rod is denoted by 15 in FIG. 1 and can be divided into individual cigarettes 16 by a rotating knife 17 . A measuring device 18 for detecting the transverse dimensions of the strand 15 is provided between the closing device 14 and the rotating knife 17 . This measuring device 18 (see FIGS . 1 and 2) has two optical scanners 19 and 20 .

These scanners 19 and 20 , of which one controls the diameter control of the strand 15 in the vertical direction and the other the diameter control of the strand 15 in the horizontal direction, are basically identical, together with the respective circuits dependent on the latter.

For this reason, the following description refers to only one of these scanners 19, 20 and the corresponding parts belonging to the two scanners 19, 20 are identified by the same reference numbers.

The two scanners 19 and 20 can include a corresponding hollow body 21 of generally cylindrical shape, which is supported in a fixed manner by the base of the confectioning machine 1 and is provided with radially arranged bores and designated 22 for the passage of the tobacco rod 15 . At one end of each hollow body 21 , a light source 23 is attached, which can consist, for example, of an infrared ray emitting diode (LED) which sends a light beam in the direction of the other end of the same hollow body 21 .

In the interior of each hollow body 21 and in a diametrically opposite position in relation to the course of the continuous strand 15 , two lenses 24 and 25 are arranged.

The lens 24 represents an optical unit for deriving the rays emitted by a light source along parallel lines to the axis of the hollow body 21 , while the lens 25 represents an optical unit for focusing the light onto a light-sensitive element or a light sensor 26 , which is located at the end of the Hollow body 21 is located, which is opposite to that provided with the light source 23 and consists of a number of scanning image sensors which belong to a "CCD array" of known type. A CCD array (charge-coupled device array) is a device which is provided with light sensors which are arranged linearly next to one another and are able to generate pulses depending on the illumination of the sensors mentioned.

With each scan, each of the photosensitive elements that make up the "CCD array" provides a signal in output of a duration proportional to the light intensity it receives. As shown in Fig. 3, there is consequently a signal A at the output of the block, which represents the photosensitive element 26 , in which two lateral bundles can be distinguished, which consist of a sequence of pulses of duration that are given by the direct Illumination on the part of the light source 23 of the photosensitive elements 26 is determined, as well as a central part consisting of pulses of shorter duration in the area of the shadow which the cigarette rod throws onto the block of the photosensitive elements 26 .

The signal A at the output from the block 26 is redirected and compared with a threshold signal of a certain value within the comparator 27 , which delivers in the output a signal B which consists of a sequence of right-angled signals corresponding to the middle part mentioned and nothing corresponding to the side bundles mentioned. The number of these right-angled pulses, the counting of which is made by the counter 28 , gives an indication of the dimension of the shadow region mentioned and definitely of the dimension of the actual diameter Φ 'of the continuous cigarette rod 15 , measured at the position of the scanner 19 and 20th

The circuit block 29 , in which the output lines of the blocks 26 of the samplers 19 and 20 converge, takes over the processing of the above-mentioned signals in the following way:
According to the solution shown in the diagram in FIG. 3, the circuit block 29 contains a block 30 , at the output of which a certain signal is present, as a function of the nominal diameter Φ of the strand 15 that is in production. This signal is sent to one of the inputs of the two comparison blocks 31, 32 with two inputs. An output signal is sent from the counters 28 to the other input of the blocks 31, 32 , each of which depends on the scanner 19 and 20 . Depending on the comparison of the signals in the input, each block 31, 32 sends out an output signal which is capable of starting a corresponding stepping motor 33, 34 in order to obtain the following phases:

• a) Rotation of the drive shaft clockwise in the case  from Φ ′ <Φ;
• b) no motor drive at Φ ′ = Φ;
• c) rotation of the drive shaft counterclockwise in Case of Φ ′ <Φ.

With reference to FIG. 2, it must be taken into account that the device 13 for correcting the transverse dimensions of the strand 15 contains two molds or bushings 38, 38 'through which the strand 15 forming in the machine passes. These molds 38, 38 'are arranged one behind the other and each consist of two openable and facing parts. In the socket 38 , the two parts are facing each other on a horizontal plane, while in the socket 38 ', the two parts are facing each other in a vertical plane. The fixed part of each of these sockets 38, 38 ', which is designated 37 , is carried by the body of the device 13 , while the movable part of each of these sockets 38, 38 ', designated 37 ', articulated on an axis 137 which is parallel to the axis of the strand 15 and is attached to the housing of the device 13 .

On each movable part 37 'a rod 36 is movably guided inside the device 13 . The free ends of the rods 36 cooperate on the path of a corresponding cam 35 on the shaft of the stepper motor 33 or on the shaft of the stepper motor 34 .

It is clear that depending on the rotation of the shaft of the motors 33 and 34 in one direction or the other, the cams 35 trigger small angular displacements for opening or closing the two bushes 38, 38 '. These displacements correspond to a smaller or larger cross-section for the passage opening of the strand 15, with the resultant reduction or enlargement of its cross-section, depending on the correction which is based on the reading of the actual diameter value of the machine coming from the scanner 19, 20 Strand 15 is running.

In this case there is a correction as a result of linear readings of "two diameters" of the strand 15 emerging from the machine, which can be referred to as horizontal and vertical

According to a solution shown in FIG. 4, the cross section of the strand 15 emerging from the machine is corrected by using only a single stepper motor 39 , and on the basis of a signal sent from block 40 for the predetermined setpoint S of the cross section of the strand 15 .

In the case shown in Fig. 4, the signals coming from the counters 28 are passed to a block 41 (e.g. a mathematical CHIP as a multiplier) which is able to process the input signals which are related to the detection of the Actual diameter of the strand 15 in the control area of the scanner 19 and 20 refer to deliver a signal at the output corresponding to the actual cross section S 'of the strand 15 , which was calculated on the basis of the signals emitted by the counters 28 . The output signal from block 40 and that from block 41 are sent to a comparison block 42 with two inputs, which is able to supply an output signal to drive the motor 39 in order to obtain the following phases:

• a ′) rotation of the drive shaft clockwise in the case from S ′ <S;
• b ′) no motor drive when S ′ = S;
• c ′) rotation of the drive shaft in the counterclockwise direction in Case of S ′ <S.

Using the solution shown in FIG. 4, the device 13 for correcting the transverse dimensions of the strand 15 can only contain a single bush 43 ( FIG. 5) or 44 ( FIG. 6), which is able to make the necessary corrections to the following Way to do:
According to FIG. 5, the sleeve 43 four section-like portions 43 a, which extend two by two opposite each other and each of which is provided with a pin 43 'which is guided in a seat which in the inner wall of on the body the device 13 attached cup flange 45 is incorporated. The cup flange 45 also forms the seat for a ring 46 , which is provided with a worm tooth section 46 a, in which a worm 47 placed on the shaft 49 of the stepping motor 39 engages.

The ring 46 has on one side a series of four grooves 48 which run in an oblique direction in relation to the direction of movement of the pins 43 ', said pins 43 ' with their free ends forming movable connecting means within the grooves 48 themselves.

It is clear that depending on the direction of rotation of the ring 46 due to the rotation of the drive shaft 49 clockwise or counterclockwise sliding of the pin 43 'in the corresponding seats in the radial direction to the socket 43 , resulting in the mutual approach or Distance of the parts 43 a results from each other and consequently a change in the cross section for the passage opening of the strand 15 that is formed .

According to what is shown in Fig. 6, the bushing or mold 44 can be of the type with a variable aperture, which contains a series of sections 44 a, which in 61 on a first, attached to the body of the device 13 ring are articulated. These sections 44 a are provided with a projection which consists of a pin 50 and is intended to fit into a corresponding groove 51 which is incorporated in a second ring (not visible) which faces the first and with the possibility of Rotation is mounted on an annular flange also attached to the body of the device 13 . This second ring can be provided with an outer section with worm teeth corresponding to an open area of the ring-like flange, into which a worm 47 engages, which, as in FIG. 5, can be placed on the shaft 49 of the stepping motor 39 .

In this case too, depending on the direction of rotation of the drive shaft 49, the sections 44 a are pivoted inwards or outwards with the bushing 44, with the resultant change in the cross section for the passage opening of the strand 15 that is being formed .

Claims (7)

1. Control and correction device for the transverse dimensions of rod-shaped products, in particular for confectioning machines for tobacco products, which has an area ( 5 ) for forming a continuous strand ( 15 ), which in the direction of advance of the strand ( 15 ) with means ( 60 ) for guiding and Folding a paper tape ( 11 ) around a filling material for the strand ( 15 ) is provided, which has an adhesive device ( 62 ) for attaching an adhesive substance to at least one longitudinal edge of the paper tape ( 11 ), which has a closing device ( 14 ) through which the Paper tape ( 11 ) can be closed around the filling material to form a continuous strand ( 15 ) and which has a measuring device ( 18 ) for detecting the transverse dimensions of the strand ( 15 ), the signals of which in a device ( 13 ) for correcting the transverse dimensions of the strand ( 15 ) can be used, characterized in that the control and correction device as a measuring device ( 18 ) Contains at least two light sensors ( 26 ) having optical scanners ( 19, 20 ) which are arranged essentially in two directions orthogonal to one another and to the direction of advance of the strand ( 15 ), the first optical scanner ( 19 ) being in one of its directions Component of the transverse dimension of the strand ( 15 ) lying orthogonally in the arrangement direction can be detected and a first signal representing this component can be generated, and wherein the second optical scanner ( 20 ) is the second component of the transverse dimension of the strand (lying in a plane orthogonal to its arrangement direction) ( 15 ) can be detected and a second signal representing this second component can be generated, that the control and correction device has a circuit ( 29 ) for processing the signals for the actual diameter generated by the two scanners ( 19, 20 ), whereby by the circuit ( 29 ) a control signal for the devices Attention ( 13 ) for correcting the transverse dimensions of the strand ( 15 ) can be generated on a target diameter, and that the device ( 13 ) controlled by this control signal for correcting the transverse dimensions of the strand ( 15 ) of stepper motors ( 33, 34; 39 ) has driven means for changing the transverse dimensions of the strand ( 15 ) in the first and the second direction. 2. Control and correction device according to claim 1, wherein the device ( 13 ) for correcting the transverse dimensions of the strand ( 15 ) has a socket or mold ( 38, 38 ') formed by two opposite parts, through which the forming strand ( 15 ) runs through, a part of the bushing or mold ( 38, 38 ′) being fastened to the surface ( 5 ) and the other part being movable relative to the first part, characterized in that at least two in succession in the direction of travel of the strand ( 15 ) arranged sockets or molds ( 38, 38 ') are provided, the first and second parts ( 37, 37 ') are each arranged orthogonally to one another, the second part ( 37 ') of each socket ( 38, 38 ') on an axis ( 137 ) is articulated, which runs parallel to the direction of travel of the strand ( 15 ) and can be adjusted relative to the first part ( 37 ) via a cam ( 35 ) mounted on the axis of the stepping motor ( 33, 34 ) is. 3. Control and correction device according to claim 1, wherein the device ( 13 ) for correcting the transverse dimensions of the strand ( 15 ) contains a socket or mold ( 43 ) through which the forming strand ( 15 ) passes, characterized in that this bushing ( 43 ) is formed from four cut-like parts ( 43 a), which are opposite each other and are linearly movable in both directions radially to the bushing ( 43 ) via a flange ( 45 ) which is rotatable from the body of the device ( 13 ) is carried and kinematically connected to the shaft ( 49 ) of the stepping motor ( 39 ), the flange ( 45 ) being provided with a series of grooves ( 48 ) which are inclined to the radial direction of movement of the cut-like parts ( 43 a) and in which with the cut-like parts ( 43 a) connected pins ( 43 ') slide, and wherein the stepper motor ( 39 ) can be controlled by the control signal generated by the circuit ( 29 ). 4. Control and correction device according to claim 1, wherein the device ( 13 ) for correcting the transverse dimensions of the strand ( 15 ) contains a bushing or mold ( 44 ) through which the forming strand ( 15 ) passes, characterized in that the bushing ( 44 ) has a diaphragm with a variable opening, which has a series of sections ( 44 a) which are angularly spaced apart from one another, which are articulated on a first ring and fastened to the body of the device and are provided with a projection ( 50 ) which engages in a corresponding groove ( 51 ) which runs in a direction which is non-concentric to the bushing ( 44 ) and is incorporated in a second ring which faces the first and is also fastened on a body of the device ( 13 ) annular flange is mounted, wherein the second ring is kinematically connected to the shaft ( 49 ) of the stepper motor ( 39 ), and wherein the step motor gate ( 39 ) can be controlled by the control signal generated by the circuit ( 29 ). 5. Control and correction device according to claims 1 or 2, characterized in that the circuit ( 29 ) has an element ( 30 ) for generating a warning signal for the desired diameter of the strand ( 15 ) being manufactured, that the circuit ( 29 ) for each optical scanner ( 19, 20 ) has a comparison block ( 31, 32 ) to which the information signal for the nominal diameter and the signal for the actual diameter generated by the optical scanners ( 19, 20 ) can be fed, and at the outputs of which the Stepper motors ( 33, 34 ) driving control signal occurs. 6. Control and correction device according to one of claims 1, 3 or 4, characterized in that the circuit ( 29 ) has an element ( 40 ) for generating an indication signal for the desired value of the cross section of the strand ( 15 ) being produced, that the circuit ( 29 ) has a processing element ( 41 ) which processes the signals generated by the optical scanners ( 19, 20 ) and generates a signal calculated from these signals and representing the actual value of the cross section of the strand ( 15 ), and that Circuit ( 29 ) has a comparison block ( 42 ) to which the information signal for the setpoint and the signal generated by the processing element ( 41 ) for the actual value are supplied, and at the output of which a signal which drives the stepper motor ( 39 ) occurs. 7. control and correction device according to at least one of the preceding claims, characterized in that each of the optical pickup (19, 20) serving for parallelization of the light emitted from a light source (23) light beams optical element (24) and a focusing of the light beams on the sensors ( 26 ) of the scanner ( 19, 20 ) serving further optical element ( 25 ).